We report a compact, scalable, and high-performance superconducting nanowire single-photon detector (SNSPD) array by using a multichannel optical fiber array-coupled configuration. For single pixels with an active area of 18 ?m in diameter and illuminated at the telecom wavelength of 1550 nm, we achieved a pixel yield of 13/16 on one chip, an average system detection efficiency of 69% at a dark count rate of 160 cps, a minimum timing jitter of 74 ps, and a maximum count rate of ?40Mcps. The optical crosstalk coefficient between adjacent channels is better than -60dB. The performance of the fiber array-coupled detectors is comparable with a standalone detector coupled to a single fiber. Our method is promising for the development of scalable, high-performance, and high-yield SNSPDs.An ideal wave-front sensor (WFS) for an adaptive optics system prioritizes three properties high sensitivity, wide dynamic range, and a linear relationship between the actual and estimated wave fronts. WFSs currently in operation can claim superiority in only two of these properties. For example, the Shack-Hartmann WFS (SHWFS) has a linear response and remains effective under large aberrations, but its sensitivity to low spatial frequencies is limited [Proc. SPIE5490, 1177 (2004)PSISDG0277-786X10.1117/12.550786]. The pyramid WFS (PyWFS) [J. Mod. Opt.43, 289 (1996)JMOPEW0950-034010.1080/09500349608232742] can also be operated in a linear control system [Opt. Express14, 11925 (2006)OPEXFF1094-408710.1364/OE.14.011925] and offers excellent sensitivity when used with an unresolved beacon but saturates quickly in the presence of large aberrations. The dynamic range can be extended by modulating the beacon about the pyramid prism tip, but at the expense of its sensitivity. This Letter describes a hybrid WFS (HyWFS) that combines the SHWFS and PyWFS, capturing the desirable features of both. The optical design of the HyWFS mimics the appearance of an unmodulated PyWFS with a lenslet array in the reimaged pupil planes. Spot patterns in the style of a SHWFS are formed in all pupil images. Wave-front estimates are calculated from the HyWFS's output using both conventional PyWFS and SHWFS reconstruction methods. A cross-over algorithm chooses between the two estimates to retain high sensitivity to low aberration and a robust capture range.We have demonstrated a Yb-doped fiber laser (YDFL) based on a multifunctional acousto-optic tunable filter (AOTF) with flexible wavelength generation capability. The number of channels, as well as their diffracted wavelengths and corresponding peak transmittances of the AOTF, can be widely tuned by changing the composite drive signal from a homemade arbitrary wave generation (AWG) board enabling single-/multi-wavelength lasing with different central wavelengths and relative intensities. The maximal wavelength tuning range and minimal resolved wavelength spacing are ?80nm and ?1.5nm, respectively, with 3 dB bandwidth less than 0.15 nm for each laser line, showing great potential for further nonlinear frequency conversion. https://www.selleckchem.com/products/GDC-0449.html To the best of our knowledge, this is the first demonstration of flexible wavelength generation from a multifunctional AOTF-based YDFL directly driven by an AWG board.High-speed spatial modulation of light is the key technology in various applications, such as optical communications, imaging through scattering media, video projection, pulse shaping, and beam steering, in which spatial light modulators (SLMs) are the underpinning devices. Conventional SLMs, such as liquid crystal (LC), digital micromirror device (DMD), and micro-electro-mechanical system (MEMS) ones, operate at a typical speed on the order of several kilohertz as limited by the slow response of the pixels. Achieving high-speed spatial modulation is still challenging and highly desired. Here, we demonstrate a one-dimensional (1D) high-speed programmable spatial light modulator based on the electro-optic effect in lithium niobate thin film, which achieves a low driving voltage of 10 V and an overall high-speed modulation speed of 5 MHz. Furthermore, we transfer an image by using parallel data transmission based on the proposed lithium niobate SLM as a proof-of-principle demonstration. Our device exhibits improved performance over traditional SLMs and opens new avenues for future high-speed and real-time applications, such as light detection and ranging (LiDAR), pulse shaping, and beam steering.A method for fabricating bio-inspired scattering substrates based on polydimethylsiloxane (PDMS) for spatially incoherent random lasing is presented. The leaves of monstera and piper sarmentosum plants are used to mold PDMS polymer to form wrinkle-like scattering substrates, which are then used with a liquid gain medium for random lasing. Scattering is attributed to the surface roughness (Sa) of the samples. The rougher sample with 5.2 ?m Sa shows a two-mode stable lasing with a 2 nm linewidth and a lower threshold fluence of 0.2mJ/cm2 compared to the sample with smaller Sa (3.6 ?m) with a linewidth of 5 nm and a threshold fluence of 0.5mJ/cm2. The waveguide theory substantiates the results of incoherent random lasing through a relation between the microstructure feature size and the mean free path. Power Fourier transform analysis is used to deduce the resonant cavity length of 180 ?m in the rougher sample, and the observed variations in cavity length with Sa validate the optical feedback. PDMS being hydrophobic, the scattering substrate can be reused by wiping off the gain medium. This Letter paves the way for facile fabrication methods of bio-inspired random lasers for sensing and imaging applications.We report the bistability of second- and third-harmonic generation in monolayer graphene plasmonics supported by graphene nanoribbon arrays. The nonlinear optical bistability of harmonic generation at the ultra-low threshold intensity ?100kW/cm2, along with the traditional linear optical bistability of transmittance, is observed due to the different local fundamental fields at the lower and higher state when the Kerr effect of graphene is considered. Importantly, the working fundamental wavelength can be tuned by the Fermi level of graphene and geometrical structure, which leads to the linear and nonlinear optical bistability available in a broadband for potential applications in advanced all-optical devices.